Hello,
Almost 3 years ago, I bought an
Elekit TU-8200R kit. I put it together as per the instructions (I'd say I have decent soldering skills) and it ran great.
After about 1 year, one channel started cracking and popping loudly, no matter the volume setting (scary!). I swapped the tubes on the left and right channels and identified that one of the 6L6GC (JJ) tubes might be defective, as the popping traveled with it. I obtained a replacement and alas, the problem was fixed.
However, now, after another 18 months or so, I again get loud popping on one channel. Unfortunately I did not note down which tube is the newer one to know whether it's the original second tube that failed, or the replacement, and whether it happened on the same channel. I ordered another one, and this time I'll make sure to mark which one is newer.
Anyway, this seems odd to me. I couldn't get a conclusive answer as to how long 6L6GC tubes usually last. Some say 2500 to 5000 hours. Others say it depends on how hard you drive them. Others say incorrect biasing affects endurance (but I don't think the TU-8200R could be adjusted). Yet others say that they've used the same tubes for decades on their (guitar) amps.
My amp is connected to a pair of Yamaha NS1000M speakers, source is a Shiit Modi+ DAC, I set the volume to about 50%, and I just listen to music about 150 days a year. Sometimes the amp runs all day. Yes, sometimes I forget to turn it off over night, so the tubes might experience the occasional 30h event. So a very generous estimate would be around 150*15 = 2250 hours per year, which is in line with
some of the sources I found.
Well, if this is indeed as expected, I'm kinda surprised this isn't highlighted more prominently in the solid state vs. tube debate. To
me, the amp sounds like any other amp. Sounds great. My main reason for buying it was to just try a tube amp and because I like assembling stuff. But I have some solid state amps from the 80s where the only problem is the occasional corroded control knob, and I've been using them just as much. They, too, sound great. I mean, I can afford it, but spending 30 bucks on a new tube every year seems weird.
If it's not expected, what could I possibly do? It works and sounds just fine most of the time. Kinda doubt there's something wrong on the inside, but I'm no expert.
Any opinions?
Thank you!
PS:
This is the assembly guide with schematics and all